On their website it says their synthetic gear oils have all different friction modifiers already in the fluid....do I still need to add the Delco limited slip friction modifier??? Thankyou.

SoCadillac

04-27-06, 05:10 PM

On their website it says their synthetic gear oils have all different friction modifiers already in the fluid....do I still need to add the Delco limited slip friction modifier??? Thankyou.
I think this is best answered by Royal Purple by calling their Tech Support and telling them the situation. They may not want other additives in their oil for a reason; then again they not have an issue with it.

diverdan

04-27-06, 08:43 PM

In the For-What-It's-Worth department. I put Amsoil synthetic gear oil in the rear of my GTO and, on the advice of the distributor, did not put the friction modifier. It has been doing fine for about 6 months now.

Dennisscars

05-01-06, 10:25 PM

9,000 miles on original diff with RP straight out of the bottle and still quiet as a stock exhaust...(but I've changed fluid 3 times)

I figure 2 qts is cheap, I change ever time I change engine oil.

Got5onit

05-02-06, 12:19 PM

You do not need to add the friction modifier when using Royal Purple.

Closer_2001

05-02-06, 12:37 PM

On their website it says their synthetic gear oils have all different friction modifiers already in the fluid....do I still need to add the Delco limited slip friction modifier??? Thankyou.

I was concerned about no additive also...

But went ahead and went with the straight Royal Purple - no additive.

I've had no issues so far with chatter or sticking of the POSI.

Seattle CTS-V

05-02-06, 12:46 PM

If my rear end goes again (which it is) will the dealership be able to tell that I have changed to a different brand of gear oil? Is there a color difference that would make it easy to spot?

ChicagoCTS32

05-02-06, 03:58 PM

Seattle: I'd be more worried about them seeing the maggie on top of the engine than the type of gear oil in your diff.

From my understanding, Royal Purple starts out purple, but turns to regular oil color after a short while.

Flyboy

05-02-06, 04:09 PM

I have the Amsoil in my diff and Amsoil's tech rep said no additive required....it's already in there...

Seattle CTS-V

05-02-06, 04:47 PM

Seattle: I'd be more worried about them seeing the maggie on top of the engine than the type of gear oil in your diff.

From my understanding, Royal Purple starts out purple, but turns to regular oil color after a short while.

My dealer installed the Maggie through their approved (read: 1/2 ownership) speed shop just around the corner.

SBONES

05-02-06, 06:31 PM

same here..i use redline. no modifier. seems ok to me.

V-Max

05-02-06, 06:59 PM

I got 27K miles on GTO and no additive is required. That includes 20 track days with RP Max Gear 80W140.

My dealer installed the Maggie through their approved (read: 1/2 ownership) speed shop just around the corner.

Ahhh, good deal for you then. They can't blame the maggie for your blown diffs.

Seattle CTS-V

05-03-06, 04:30 PM

Ahhh, good deal for you then. They can't blame the maggie for your blown diffs.

I wish that were 100% true...but, it does make it harder for them to deny my warranty claims b/c they "promised" to take care of me. So far, they really have! From the beginning, they've acknowledged the fact that this car has a weak rear even w/ stock power output.